JP6534952B2 - Terminal apparatus and transmission order determination method - Google Patents

Description

  The present invention relates to a terminal device and a transmission order determination method.

  A PON (Passive Optical Network) is configured by connecting an Optical Line Terminal (OLT) and a plurality of ONUs (Optical Network Unit). FIG. 9 is a diagram showing an example of the configuration of a PON system. In the figure, the OLT and M (M is an integer of 2 or more) ONUs of ONU # 1 to ONU # M are connected by a relay network using an optical fiber and an optical splitter.

  FIG. 10 is a diagram showing a bandwidth allocation procedure by a PON system adopting a time division multiplexing (TDM) scheme. T on the horizontal axis represents time. As shown in the figure, when transmitting data signals from ONU # 1 to ONU # M (M = 4 in the figure) to the OLT by time division multiplexing, the OLT permits transmission to ONU # 1 to ONU # M. Sends a control signal to be given. The transmission permission indicates the time and capacity in which the ONU can transmit data signals to the OLT. On the basis of the control signal, the ONU transmits a data signal of the capacity instructed at a time instructed by the OLT to the OLT (see, for example, Non-Patent Document 1). In the figure, the transmission order (time) is designated in the order of ONU # 1, ONU # 4, ONU # 2, ONU # 3 by the control signal.

  As shown in the figure, when a plurality of ONU # 1 to ONU # 4 are connected to the OLT, the ONU # 1 that transmitted the data signal first and the ONU # 3 that transmitted the data last transmit the data signal to the OLT. There is a difference in the time of arrival of This time difference is a delay. This time difference is defined as transmission waiting time. That is, the transmission standby time is the time when the OLT waits from the arrival time of the data signal transmitted by the ONU of transmission order No. 1 to the arrival time of the data signal transmitted by the ONUs of the second and subsequent transmission orders. In other words, the transmission standby time is also the time from the time when the ONU of transmission order No. 1 transmits the data signal to the time when the ONUs of the second or subsequent transmission order transmit the data signal of the own apparatus. A technique for fairing the delay due to this transmission waiting time has already been proposed (see, for example, Non-Patent Document 2). In addition to this proposed technique, it is possible to make transmission waiting time fair among a plurality of ONUs by applying a generally known round robin method.

  FIG. 11 is a diagram showing an example of data signal transmission in the PON system when using the round robin method. In the round robin scheme, the order of transmission is shifted after data transmission of each ONU is completed. At the next transmission timing, the ONU that has transmitted the data signal first is set to transmit the data signal last, and the transmission order is advanced. In the figure, round robin is performed after transmission of ONU has made one round, but round robin after transmission is repeated several times can achieve fairness in the long run. . A cycle for changing the transmission order is defined as a transmission order fairing cycle.

International Publication No. 2014/077168

"NTT Technical Journal, Basic Technology Course [GE-PON technology], 3rd DBA function", [online], 2005, Nippon Telegraph and Telephone Corporation, [December 21, 2015 search], Internet <http: //www.ntt.co.jp/journal/0510/files/jn200510067.pdf> Joki Miki, Shin-ichi Aoyagi, Yusuke Ueda, Takashi Watanabe, "Proposal of Shared Access Method for Passive Double Star Optical Access System", Transactions of the Institute of Electronics, Information and Communication Engineers B, September 2001, Vol. J84-B, No .9, p. 1578-1586 “C-RAN The Road Towards Green RAN”, [online], October 2011, China Mobile Research Institute, [Search on February 5, 2016], Internet <http://labs.chinamobile.com/cran/ > “Further Study on Critical C-RAN Technologies”, Next Generation Mobile Networks (NGMN) Alliance, March 2015, version 1.0 “Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2”, 3GPP TS 36.300, v 12.4.0, December 2014 K. Miyamoto, S. Kuwano, J. Terada, A. Otaka, “Split-PHY Processing Architecture to Realize Base Station Coordination and Transmission Bandwidth Reduction in Mobile Fronthaul”, Optical Fiber Communications Conference and Exhibition (OFC), March 2015 , M2J.4.

  There is a case where fairness is not secured in the PON section when devices connected to the PON system transmit and receive traffic having a periodicity different from the transmission order fairing period. As an example corresponding to this case, it is conceivable that the mobile radio base station is accommodated by the PON system. The mobile radio base station has a configuration called C-RAN (Centralized-Radio Access Network). In the C-RAN configuration, the mobile radio base station is separated into a radio antenna unit (RRH: Remote Radio Head) and a signal processing unit (BBU: Baseband Unit), and the BBU-RRH are connected by an optical fiber (for example, Non-Patent Document 3). It has been studied to configure this BBU-RRH with a PON topology (see, for example, Patent Document 1). Recently, a C-RAN configuration has been proposed in which all or part of the physical layer functions are aggregated in RRH and the functions in the MAC layer and higher are aggregated in BBU (see Non-Patent Document 4, Non-Patent Document 6). In the schemes of Non-Patent Document 4 and Non-Patent Document 6 etc., the RRH demodulates the data signal for each sub-frame, and in some cases performs further decoding, and transfers the data signal to the BBU. An example of a sequence for transferring data signals assumed in this method is shown in FIG.

  FIG. 12 is a diagram showing an example of a sequence in which the RRH transfers a data signal received from a wireless terminal to the BBU. The RRH demodulates and decodes a signal received from a wireless terminal. Signals demodulated and decoded in RRH are queued in subframe length units and transferred to BBU. In the case of an LTE (Long Term Evolution) mobile system, the subframe length is 1 ms (see Non-Patent Document 5). From this, when transferring the data signal from the RRH to the BBU, the data queuing period starts at 1 ms. Data is queued to the RRH and transferred with 1 ms as one cycle.

  FIG. 13 is a diagram showing a transfer sequence when the mobile radio base station is accommodated in the PON system. The ONU transmits the data of the mobile system received from the RRH to the OLT using the band allocated in the transmission cycle in synchronization with the transmission cycle of the data signal of the PON. The ONU performs transmission over the next transmission cycle if the allocated bandwidth within the transmission cycle is smaller than the data amount of the mobile system.

  As in the above example, when the connected devices have periodicity, the order of data transmission from each ONU may not be fair in the PON system. FIG. 14 is a diagram showing the transmission order and transmission data amount of the ONU when the mobile radio base station is accommodated in the PON system. The figure shows the case where the bandwidth allocated to the ONU is applied to a plurality of transmission order fairing cycles. For example, when the transmission period of the data signal of the connected device (RRH) is 1 ms and the transmission order fairing period is 250 μs, the number of ONUs connected to the OLT is 2, 4, 8, ... (data signal In the case of a transmission cycle / an integral multiple of the transmission order fairing cycle), traffic is unevenly distributed at the beginning of a subframe cycle every 1 ms. As shown in FIG. 14, traffic is concentrated at the timing of transmission order fairness cycle of transmission order ONU # 1 → ONU # 2 → ONU # 3 → ONU # 4, and the transmission order is not fair. That is, as described above, when traffic can not transmit queued data in one transmission order fairing cycle due to traffic concentration, the ONU transmits data over the next transmission order fairing cycle. Do. However, in round robin, since the transmission order is assigned regardless of the presence or absence of data to be transmitted, an ONU having data to be transmitted may be a later transmission order than an ONU having no data to be transmitted. Therefore, there may be an ONU in which the transmission waiting time becomes long. Also, the average transmission order of each ONU may be biased.

  In view of the above-mentioned circumstances, the present invention aims to provide an end station apparatus and a transmission order determination method capable of determining the transmission order of the termination apparatus so as to reduce the deviation of the transmission standby time.

  One aspect of the present invention is a terminal device connected to a plurality of terminal devices, and acquires information on transmission order or transmission data amount when there is transmission data of each of the terminal devices in a plurality of cycles, A transmission order determination unit that determines a transmission order of the termination apparatus based on an average of the transmission order of each of the termination apparatuses or a total of the transmission data amount; and the termination apparatus according to the transmission order determined by the transmission order determination unit And a transmission order instruction unit for instructing the order of data transmission.

  Further, one aspect of the present invention is the terminal apparatus described above, wherein the transmission order determination unit transmits the transmission order of the terminal apparatus in ascending order of the average of the transmission order or in ascending order of the total transmission data amount. decide.

  Further, one aspect of the present invention is the terminal station apparatus described above, wherein the transmission order determination unit acquires information of transmission order data of each of the terminal apparatuses and information of transmission data amount in a plurality of cycles, For each terminal device, the presence or absence of transmission data is determined based on the transmission data amount of each cycle, and the average of the transmission order in the cycle determined to be transmission data is calculated.

  Further, one aspect of the present invention is the terminal device as described above, wherein the transmission order determination unit calculates an average difference in transmission order among the different terminal devices, and the sum of the differences exceeds a threshold. The transmission order of the termination device is newly determined.

  Moreover, 1 aspect of this invention is the above-mentioned terminal | end station apparatus, Comprising: The said transmission order determination part acquires the said transmission data amount based on the data amount received from the said termination device.

  Further, one aspect of the present invention is the terminal apparatus described above, wherein the transmission order determination unit acquires the transmission data amount based on the bandwidth requested from the termination apparatus, and the transmission order determination unit It further comprises a data amount acquisition unit to notify.

  In the above-mentioned terminal station apparatus, the period is a period for changing the transmission order of the terminal device.

  Further, one aspect of the present invention is a transmission order determination method executed by an end station apparatus connected to a plurality of end apparatuses, which is information on the transmission order when there is transmission data of each of the end apparatuses in a plurality of cycles or A transmission order determining step of acquiring transmission data amount information and determining a transmission order of the termination device based on an average of the transmission order of each of the termination devices or a total of the transmission data amount; And a transmission order instruction step of instructing the end device in the order of data transmission in accordance with the determined transmission order.

  According to the present invention, it is possible to determine the transmission order of the end device so as to reduce the deviation of the transmission waiting time.

It is a figure showing an example of composition of a network system by a 1st embodiment of the present invention. It is a block diagram which shows the structure of OLT by the embodiment. It is a flowchart which shows the operation | movement algorithm of OLT by the embodiment. It is a block diagram showing composition of OLT by a 2nd embodiment. It is a figure which shows the sequence of notification of report information in the network system by the embodiment. It is a block diagram showing composition of OLT by a 3rd embodiment. It is a flowchart which shows the operation | movement algorithm of OLT by the embodiment. It is a block diagram which shows the structure of OLT by 4th Embodiment. It is a figure which shows the structural example of a PON system. It is a figure which shows the procedure of the band allocation by the PON system which employ | adopts a time division multiplex system. It is a figure which shows the example of the data signal transmission in the PON system at the time of using a round robin system. It is a figure which shows the example of a sequence which transfers the data signal which RRH received from the radio | wireless terminal to BBU. It is a figure which shows the sequence of a transfer when the radio | wireless base station for mobiles is accommodated in a PON system. It is a figure which shows the transmission order and transmission data amount of ONU when accommodating the radio | wireless base station for mobiles in a PON system. It is a block diagram showing composition of OLT to which an embodiment of the present invention is not applied.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

First Embodiment
FIG. 1 is a diagram showing a configuration example of a network system 1 according to a first embodiment of the present invention. In the network system 1 shown in the figure, for example, the PON system shown in FIG. 9 relays data between connected external devices which are external devices connected to the PON system. The PON system includes an OLT (Optical Line Terminal; optical subscriber line termination device) 100 as an end station device, and an ONU (Optical Network Unit) of M units (M is an integer of 2 or more) as an end device. And the network device 200). In the following, although the case where the connection external device is the BBU (signal processing unit: Baseband Unit) 610 and the RRH (antenna unit: Remote Radio Head) 620 of the mobile radio base station will be described as an example, the connection external device is It is not limited to the mobile radio base station. Hereinafter, the mth (m is an integer of 1 or more and M or less) ONU 200 will also be described as ONU 200 #m.

  The OLT 100 and the M ONUs 200 are connected by distributing a communication signal transmitted by one optical fiber 710 into a plurality of parts by the optical splitter 720. The OLT 100 multiplexes and transmits signals (downlink signals) to be transmitted to the M ONUs 200 according to a TDM (time division multiplex) method, and the optical splitter 720 transfers the multiplexed downstream signals to the respective ONUs 200 as they are. Signals (uplink signals) transmitted from the M ONUs 200 to the OLT 100 are multiplexed by the optical splitter 720 and transmitted to the OLT 100.

  In this embodiment, when the bandwidth transmitted from the ONU 200 to the OLT 100 is shared by a plurality of ONUs 200 by time division, the order in which each ONU 200 transmits data is made fair so that the transmission standby time is not biased. Therefore, the OLT 100 monitors the transmission order of data signals transmitted from each ONU 200, and when the transmission order is unfair, changes the transmission order so as not to bias the delay.

  FIG. 15 is a block diagram showing the configuration of an OLT 900 to which this embodiment is not applied. In the figure, the OLT 900 comprises a downstream frame processor 920, an E / O data amount acquirer 930, an O / E data amount acquirer 940, an upstream frame processor 950, and a transmission order commander 960. Configured

  The downstream frame processing unit 920 converts the downstream signal frame received from the BBU 610 into a frame used in the PON system. The E / O data amount acquisition unit 930 converts the downstream signal, which has been frame-converted by the downstream frame processing unit 920, from an electrical signal to an optical signal, and outputs the optical signal to an optical fiber between the ONU and the ONU. The O / E data amount acquisition unit 940 receives an optical signal transmitted by an optical fiber between itself and the ONU, converts the optical signal into an electrical signal, and outputs the electrical signal to the upstream frame processing unit 950. The upstream frame processing unit 950 transforms the frame of the upstream signal converted into the electric signal by the O / E data amount acquisition unit 940 from the PON frame to a desired frame, and outputs the frame to the BBU. The transmission order instruction unit 960 generates a transmission order instruction signal and transmits the transmission order instruction signal to the ONU 200. The transmission order instruction signal is a control signal for instructing the transmission order by designating the timing at which the ONU 200 is permitted to transmit the upstream signal by using a time or the like.

  FIG. 2 is a block diagram showing the configuration of the OLT 100 according to the first embodiment of the present invention. The OLT 100 includes a downstream frame processing unit 120, an E / O data amount acquisition unit 130, an O / E data amount acquisition unit 140, an upstream frame processing unit 150, a transmission order determination unit 160, a transmission order instruction unit 170, and It is configured with. The downlink frame processing unit 120, the E / O data amount acquisition unit 130, the O / E data amount acquisition unit 140, the uplink frame processing unit 150, and the transmission order command unit 170 respectively have the downlink frame processing unit 920 shown in FIG. It has the same function as the O data amount acquisition unit 930, the O / E data amount acquisition unit 940, the upstream frame processing unit 950, and the transmission order command unit 960. The transmission order determination unit 160 calculates an index value representing the fairness of the transmission order of the ONU 200. When the transmission order determination unit 160 determines that the transmission order is not fair based on the index value, it calculates the transmission order of each ONU 200 and outputs the calculation result to the transmission order command unit 170. The transmission order instructing unit 170 determines the transmission timing of the uplink data of each ONU 200 according to the transmission order of the ONU 200 notified as the calculation result from the transmission order determination unit 160, and transmits the transmission order instruction signal instructing the determined transmission timing to the ONU 200. Send.

FIG. 3 is a flowchart showing an operation algorithm of the OLT 100 according to the present embodiment.
First, the transmission order determination unit 160 acquires the number M of ONUs, which is the number of ONUs 200 connected to the own device (step S105). Next, the transmission order determination unit 160 sets the number N of transmission order fairing cycles for acquiring information to determine the fairness of the transmission order, and the judgment threshold D _th of fairness. Furthermore, the transmission order determination unit 160 sets an initial value N to the number N (x) of transmission order fairing cycles in which each ONU 200 transmits data in the first to Nth transmission order fairing cycles (step S110). ). Here, x (x is an integer of 1 or more and M or less) indicates the ONU 200 number. That is, the x-th ONU 200 is the ONU 200 #x.

  The transmission order command unit 170 of the OLT 100 performs fair control such as a round robin method as an initial operation (step S115). After the transmission order fairing cycle reaches N times, the transmission order determination unit 160 calculates an index value indicating whether the transmission order of each ONU 200 is set fairly. Therefore, transmission order determination unit 160 determines the amount of data V (x, n) and transmission order O of ONU 200 # 1 to ONU 200 # m for each transmission order fairing cycle from the first transmission order fairing cycle to the Nth transmission order. Get (x, n). n (an integer greater than or equal to 1 and less than or equal to N) is a variable representing what number of transmission order fairing cycle among the N transmission order fairing cycles. The data amount V (x, n) is the amount of data transmitted from the ONU 200 #x to the OLT 100 in the nth transmission order fairing cycle. The transmission order O (x, n) is the order of data transmission of the ONU 200 #x in the n-th transmission order fairing cycle.

  The transmission order determination unit 160 selects M ONUs 200 one by one (step S125), and executes the processing of the following steps S130 and S135. The number of ONU 200 selected in step S125 is x.

  The transmission order determination unit 160 acquires the transmission orders O (x, 1) to O (x, N) of the first to Nth transmission cycles instructed from the transmission order command unit 170 to the ONU 200 #x. Furthermore, the transmission order determination unit 160 acquires, from the upstream frame processing unit 150, the data amounts V (x, 1) to V (x, N) received from the ONU 200 #x in each of the 1st to Nth transmission cycles.

The transmission order determination unit 160 sets O (x, n) = 0 when V (x, n) = 0. Also, the transmission order determination unit 160 obtains the number L (x) of transmission order fairing cycles where V (x, n) = 0, and sets the value of N (x) to N (x) −L ( Update by x) (step S130). The transmission order determination unit 160 calculates the average value W _x of the transmission order of the ONU 200 #x when there is transmission data in N transmission order fairing cycles according to the following equation (1) (step S 135).

As described above, the transmission order determination unit 160 calculates W _x for all the M ONUs 200 connected to the OLT 100. It can be said that the closer the difference in W _x between M ONUs 200 is to zero, the higher the fairness.
As shown in the following equation (2), the difference in W _x between the ONU 200 #i and the ONU 200 #j (j) i) is D _ij (i, j is an integer of 1 or more and M or less).

If D _ij is close to 0, fairness is high. The transmission order determination unit 160 obtains the sum of D _ij for all the combinations of ONUs 200 as shown in the following equation (3), and uses it as an index value indicating whether the transmission order is set fairly (step S140) .

Transmission order determination unit 160 determines whether index value D is larger than threshold value D _th (step S145). The transmission order command unit 170 determines that the fairness is high when the index value D is less than or equal to the threshold D _th (step S145: NO). The transmission order instructing unit 170 continues to use the current transmission order of the ONU 200.

On the other hand, the transmission order determination unit 160, if the index value D has a value greater than the threshold _{D th} (step S145: YES), _{W x} is re-sort the sending order of each ONU200 in decreasing order (step S150). The transmission order determination unit 160 outputs the order of the new ONU 200 after the re-sorting to the transmission order command unit 170. The transmission order instructing unit 170 performs fair control such as round robin based on the order of the ONUs 200 after the resorting.

Note that the determination threshold value D _th may be a variable of N because the value changes depending on the number N of transmission order fairing cycles.
The transmission order determination unit 160 can also determine the transmission order of each ONU 200 based on the order in which data signals are sent from the ONU 200 to the OLT 100. In this case, the transmission order determination unit 160 acquires information on the transmission order of each ONU 200 from the upstream frame processing unit 150. Since the transmission order of the ONUs 200 is determined in the OLT 100, the transmission order determination unit 160 can also read the information in the OLT 100 from the transmission order instruction unit 170 as described above.

Second Embodiment
In the first embodiment, the data amount V (x, n) transmitted from each ONU 200 is acquired based on the data signal from the ONU 200 received by the upstream frame processing unit 150. In the second embodiment, report information sent from each ONU 200 is used instead of the data amount V (x, n) referred to in the first embodiment. The report information is information transmitted from the ONU 200 when the OLT 100 allocates a bandwidth to each ONU 200, and the bandwidth requested by the ONU 200 is set. In the following, differences from the first embodiment will be described. The configuration of the network system of this embodiment is a configuration in which the OLT 100 in the network system 1 shown in FIG. 1 is replaced with the OLT 100a shown in FIG.

  FIG. 4 is a block diagram showing the configuration of the OLT 100 a according to the second embodiment. In the figure, the same components as those of the OLT 100 according to the first embodiment shown in FIG. The difference between the OLT 100 a and the OLT 100 shown in FIG. 2 is that the OLT 100 a further includes a data amount acquisition unit 155. The data amount acquisition unit 155 acquires report information received from each ONU 200 from the upstream frame processing unit 150. The data amount acquisition unit 155 converts the information of the required bandwidth set in the acquired report information into the data amount V (x, n), and outputs the data amount to the transmission order determination unit 160. For example, the required bandwidth information may be the data amount itself, or may be bandwidth per unit time or transmission order fairing cycle.

FIG. 5 is a diagram showing a sequence of notification of report information in the network system of this embodiment.
Each ONU 200 transmits a report signal in which report information is set to the OLT 100 a in order to request bandwidth allocation. When there is no data to be transmitted to the OLT 100a, the ONU 200 transmits report information indicating that there is no required bandwidth. When the ONU 200 receives data to be transmitted to the OLT 100 a from the RRH 620, the ONU 200 stores the received data in a buffer. The ONU 200 sets a required bandwidth corresponding to the buffered data amount as report information, and transmits a report signal.

  The data amount acquisition unit 155 of the OLT 100 a acquires report information from the report signal received by the upstream frame processing unit 150. The data amount acquisition unit 155 outputs the report information to the transmission order instruction unit 170, and calculates the amount of data to be transmitted from the ONU 200 that is the transmission source of the report signal based on the required bandwidth set in the report information. It is output to the determination unit 160. The operation of the transmission order determination unit 160 other than receiving the data amount from the data amount acquisition unit 155 is the same as that of the first embodiment. The transmission order instructing unit 170 determines the allocation bandwidth of each ONU 200 based on the required bandwidth set in the report information received from each ONU 200. The transmission order instructing unit 170 determines the transmission time of the upstream signal of each ONU 200 based on the determined allocation band of the ONU 200 and the transmission order of the ONU 200 notified from the transmission order determination unit 160. The transmission order instructing unit 170 transmits, to each ONU 200, a transmission permission signal in which the transmission time and the allocation band of the ONU 200 are set. The ONU 200 transmits the buffered upstream data to the OLT 100 a in accordance with the allocation band and the transmission order notified by the transmission permission signal.

Third Embodiment
In the first embodiment and the second embodiment, fairness control of transmission order is performed based on the order O (x, n) of data transmission. However, even if the transmission order is made fair, the transmission waiting time may vary depending on the amount of data sent from each ONU. For example, it is assumed that a PON system having a usable bandwidth of 10 Gbps (gigabits per second) accommodates the ONU 200 # 1, the ONU 200 # 2, the ONU 200 # 3, and the ONU 200 # 4. Assuming that ONU 200 # 1 and ONU 200 # 2 always occupy 1 Gbps or more and ONU 200 # 3 and ONU 200 # 4 use bands of about several Mbps, even if the transmission order is made fair, ONU 200 # 3 and ONU 200. The transmission waiting time of # 4 is longer than ONU 200 # 1 and ONU 200 # 2. This proves that the transmission waiting time is not faired. Therefore, in the present embodiment, the transmission order is determined based on the data amount V (x, n) of the signal transmitted from each ONU 200. Hereinafter, differences from the first embodiment will be mainly described.

The configuration of the network system of this embodiment is a configuration in which the OLT 100 in the network system 1 shown in FIG. 1 is replaced with an OLT 100 b shown in FIG.
FIG. 6 is a block diagram showing the configuration of an OLT 100b according to the third embodiment. In the figure, the same components as those of the OLT 100 according to the first embodiment shown in FIG. The OLT 100 b differs from the OLT 100 shown in FIG. 2 in that a transmission order determination unit 160 b is provided instead of the transmission order determination unit 160. The transmission order determination unit 160 b determines the transmission order based on the data amount V (x, n) of the signal transmitted from each ONU 200.

  FIG. 7 is a flowchart showing an operation algorithm of the OLT 100 b of the present embodiment. First, the transmission order determination unit 160b acquires the number M of ONUs, which is the number of ONUs 200 connected to the own device (step S305). Next, the transmission order determination unit 160b sets the number N of transmission order fairing cycles for acquiring information (step S310). The transmission order command unit 170 performs fair control such as a round robin method as an initial operation (step S315). The transmission order determination unit 160b determines the transmission order of each ONU 200 after the transmission order fairing cycle reaches N times. Therefore, the transmission order determination unit 160b acquires, from the upstream frame processing unit 150, the data amounts V (x, 1) to V (x, N) received from the ONU 200 #x in each of the 1st to Nth transmission cycles Step S320).

The transmission order determination unit 160b selects M ONUs 200 one by one (step S325), and executes the process of step S340 described below. The number of ONU 200 selected in step S320 is x. The transmission order determination unit 160 b obtains the sum S _x of the data amounts V (x, n) for N times of the transmission order fairing cycle of the ONU 200 #x (step S 330).

The transmission order determination unit 160 b calculates the total sum S _x for the number of M ONUs 200 connected. Transmission sequence determining unit 160b compares the respective sum _S 1 to S _M between each ONU200 # 1~ONU200 # M, the sum _{S x} is sorted ONU 200 in ascending order as the transmission order (step S335). For example, in the PON system accommodating the ONU 200 # 1, the ONU 200 # 2, the ONU 200 # 3, and the ONU 200 # 4, when S ₁ <S ₃ <S ₂ <S ₄ , the transmission order of the ONU 200 # 1 and the ONU 200 # 3 Are set to first and second, and ONU 200 # 2 and ONU 200 # 4 are set to third and fourth. The transmission order determining unit 160b fixes the transmission order to this state, and after determining that the transmission standby time has been equalized, instructs the transmission order instructing unit 170 to perform fair control such as round robin again.

Fourth Embodiment
In the third embodiment, the transmission order is changed using the information of the data amount V (x, n) acquired from the upstream frame processing unit 150. However, as in the second embodiment, the transmission is performed from the ONU 200. It is possible to acquire the data amount V (x, n) also from the report information that In the following, differences from the third embodiment will be described. The configuration of the network system of this embodiment is a configuration in which the OLT 100 in the network system 1 shown in FIG. 1 is replaced with an OLT 100 c shown in FIG.

  FIG. 8 is a block diagram showing the configuration of an OLT 100c according to the fourth embodiment. In the figure, the same components as those of the OLT 100b according to the third embodiment shown in FIG. The difference between the OLT 100 c and the OLT 100 b shown in FIG. 6 is that the OLT 100 c further includes a data amount acquisition unit 155. The data amount acquisition unit 155 performs the same processing as the data amount acquisition unit 155 included in the OLT 100 a according to the second embodiment shown in FIG. 4. That is, the data amount acquisition unit 155 of the OLT 100 c acquires the report information set in the report signal received by the upstream frame processing unit 150. The data amount acquisition unit 155 outputs the report information to the transmission order instruction unit 170, and calculates the amount of data to be transmitted from the ONU 200 that is the transmission source of the report signal based on the required bandwidth set in the report information. It outputs to the determination part 160b. The subsequent operation is similar to that of the third embodiment.

Fifth Embodiment
The first to fourth embodiments described above can be used not only in combination but also in arbitrary combination.

  As described above, in the OLT (terminal apparatus) connected to a plurality of ONUs (termination apparatus), the transmission order determination unit transmits information or transmission of the transmission order when there is transmission data of each ONU in a plurality of cycles. Information on the amount of data is acquired, and the transmission order of each ONU is determined based on the average of the transmission order of each ONU or the sum of the amount of transmission data. Specifically, the transmission order determination unit determines the transmission order of ONUs in the order of low average transmission order or in order of small total transmission data amount. The cycle is a transmission order fairing cycle for changing the transmission order of ONUs. The transmission order determination unit acquires transmission order information of each ONU data and transmission data amount information in a plurality of transmission order fairing cycles, and transmits data for each ONU based on the transmission data amount of each cycle. The presence or absence is determined, and the average of the transmission order in the cycle determined to have transmission data is calculated. Also, the transmission order determination unit may calculate an average difference between transmission orders among different ONUs, and newly determine the transmission order of ONUs when the sum of the calculated differences exceeds a threshold. The transmission order determination unit may acquire the transmission data amount based on the data amount received from the ONU, and the data amount acquisition unit acquires the transmission data amount based on the bandwidth requested from the ONU, and determines the transmission order You may notify the department. The transmission order command unit of the OLT instructs the ONU on the order of data transmission based on the transmission order determined by the transmission order determination unit.

  Conventionally, due to the periodicity of data signal transmission of a device connected to the PON system, the fairness of transmission waiting time in the ONU may be impaired in the PON system. According to the above-described embodiment, the transmission order of each ONU is determined based on the transmission order or data amount of the signal transmitted from the ONU so as to reduce the bias of the transmission waiting time. This makes it possible to improve the fairness of the transmission standby time between ONUs due to the transmission order.

  Some functions of the OLTs 100, 100a, 100b, and 100c in the above-described embodiment may be realized by a computer. In that case, a program for realizing this function may be recorded in a computer readable recording medium, and the program recorded in the recording medium may be read and executed by a computer system. Here, the “computer system” includes an OS and hardware such as peripheral devices. The term "computer-readable recording medium" refers to a storage medium such as a flexible disk, a magneto-optical disk, a ROM, a portable medium such as a ROM or a CD-ROM, or a hard disk built in a computer system. Furthermore, “computer-readable recording medium” dynamically holds a program for a short time, like a communication line in the case of transmitting a program via a network such as the Internet or a communication line such as a telephone line. It may also include one that holds a program for a certain period of time, such as volatile memory in a computer system that becomes a server or a client in that case. The program may be for realizing a part of the functions described above, or may be realized in combination with the program already recorded in the computer system.

  The embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration is not limited to this embodiment, and includes design and the like within the scope of the present invention.

  It can be used for a system that communicates by multiple access.

1 Network system 100, 100a, 100b, 100c OLT
120, 920 downlink frame processing unit 130, 930 E / O data amount acquisition unit 140, 940 O / E data amount acquisition unit 150, 950 upstream frame processing unit 155 data amount acquisition unit 160, 160b transmission order determination unit 170, 960 transmission Order command unit 200 ONU
610 BBU
620 RRH
710 Optical Fiber 720 Optical Splitter

Claims (8)

A terminal device connected to a plurality of terminal devices,
The transmission order information or transmission data amount information when there is transmission data of each of the terminal devices in a plurality of cycles is acquired, and the terminals are based on the average of the transmission order of the terminal devices or the total of the transmission data amounts. A transmission order determination unit that determines the transmission order of the devices;
A transmission order instruction unit that instructs the end device on the order of data transmission according to the transmission order determined by the transmission order determination unit;
Equipped with
The transmission order determination unit determines the transmission order of the termination apparatus in the order of low average transmission order or in the order of small total transmission data amount.
An end station apparatus characterized by A terminal device connected to a plurality of terminal devices,
A transmission order determination unit that acquires information on the transmission order when there is transmission data of each of the termination apparatuses in a plurality of cycles, and determines the transmission order of the termination apparatuses based on an average of the transmission orders of the termination apparatuses;
A transmission order instruction unit that instructs the end device on the order of data transmission according to the transmission order determined by the transmission order determination unit;
Equipped with
The transmission order determination unit acquires transmission order information and transmission data amount information of data of each of the terminal devices in a plurality of cycles, and transmits data of transmission data based on the transmission data amount of each cycle for each of the terminal devices. Determining presence / absence and calculating an average of the transmission order in a cycle determined to have transmission data present;
Termination you wherein a. A terminal device connected to a plurality of terminal devices,
The transmission order information or transmission data amount information when there is transmission data of each of the terminal devices in a plurality of cycles is acquired, and the terminals are based on the average of the transmission order of the terminal devices or the total of the transmission data amounts. A transmission order determination unit that determines the transmission order of the devices;
A transmission order instruction unit that instructs the end device on the order of data transmission according to the transmission order determined by the transmission order determination unit;
Equipped with
The transmission order determination unit calculates an average difference in transmission order among the different terminal devices, and newly determines the transmission order of the terminal devices if the sum of the differences exceeds a threshold.
Termination you wherein a. The transmission order determination unit acquires the transmission data amount based on the data amount received from the termination device.
The terminal apparatus according to any one of claims 1 to 3 , characterized in that: It further comprises a data amount acquisition unit for acquiring the transmission data amount based on the bandwidth requested from the termination device and notifying the transmission order determination unit of the transmission data amount.
The terminal apparatus according to any one of claims 1 to 4 , characterized in that: A transmission order determination method executed by an end device connected to a plurality of end devices, comprising:
The transmission order information or transmission data amount information when there is transmission data of each of the terminal devices in a plurality of cycles is acquired, and the terminals are based on the average of the transmission order of the terminal devices or the total of the transmission data amounts. A transmission order determination step of determining a transmission order of the devices;
A transmission order instruction step of instructing the end device in the order of data transmission according to the transmission order determined in the transmission order determination step;
I have a,
In the transmission order determination step, the transmission order of the end device is determined in the order of low average transmission order or in the order of small total transmission data amount,
A transmission order determination method characterized in that. A transmission order determination method executed by an end device connected to a plurality of end devices, comprising:
A transmission order determination step of acquiring information on the transmission order when there is transmission data of each of the terminal devices in a plurality of cycles, and determining the transmission order of the terminal devices based on the average of the transmission order of the terminal devices;
A transmission order instruction step of instructing the end device in the order of data transmission according to the transmission order determined in the transmission order determination step;
Have
In the transmission order determination step, information on transmission order data and transmission data amount of each terminal device in a plurality of cycles is acquired, and transmission data is obtained based on the transmission data amount of each cycle for each terminal device. Determining the presence or absence of the transmission order, and calculating the average of the transmission order in the cycle determined to have the transmission data presence,
A transmission order determination method characterized in that. A transmission order determination method executed by an end device connected to a plurality of end devices, comprising:
The transmission order information or transmission data amount information when there is transmission data of each of the terminal devices in a plurality of cycles is acquired, and the terminals are based on the average of the transmission order of the terminal devices or the total of the transmission data amounts. A transmission order determination step of determining a transmission order of the devices;
A transmission order instruction step of instructing the end device in the order of data transmission according to the transmission order determined in the transmission order determination step;
Have
In the transmission order determination step, a difference in average transmission order among the different end devices is calculated, and the transmission order of the end devices is newly determined if the sum of the differences exceeds a threshold.
A transmission order determination method characterized in that.

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